Hemorrhagic regression of melanoma metastases during therapeutic vaccination: a report of three cases

Spin Trapping of Nitric Oxide by Hemoglobin and Ferrous Diethyldithiocarbamate in Model Tumors Differing in Vascularization

Animal tumors serve as reasonable models for human cancers. Both human and animal tumors often reveal triplet EPR signals of nitrosylhemoglobin (HbNO) as an effect of nitric oxide formation in tumor tissue, where NO is complexed by Hb. In search of factors determining the appearance of nitrosylhemoglobin (HbNO) in solid tumors, we compared the intensities of electron paramagnetic resonance (EPR) signals of various iron-nitrosyl complexes detectable in tumor tissues, in the presence and absence of excess exogenous iron(II) and diethyldithiocarbamate (DETC). Three types of murine tumors, namely, L5178Y lymphoma, amelanotic Cloudman S91 melanoma, and Ehrlich carcinoma (EC) growing in DBA/2 or Swiss mice, were used. The results were analyzed in the context of vascularization determined histochemically using antibodies to CD31. Strong HbNO EPR signals were found in melanoma, i.e., in the tumor with a vast amount of a hemorrhagic necrosis core. Strong Fe(DETC)2NO signals could be induced in poorly vascularized EC. In L5178Y, there was a correlation between both types of signals, and in addition, Fe(RS)2(NO)2 signals of non-heme iron-nitrosyl complexes could be detected. We postulate that HbNO EPR signals appear during active destruction of well-vascularized tumor tissue due to hemorrhagic necrosis. The presence of iron-nitrosyl complexes in tumor tissue is biologically meaningful and defines the evolution of complicated tumor-host interactions.

Sentinel bruising as a presentation of metastatic melanoma

A 46-year-old man presented with a 4-week history of bruising with subcutaneous nodules and weight loss. He also had a 2-week history of progressive back and hip pain. He had been diagnosed with stage Ib cutaneous melanoma 30 months previously, which had been fully excised. A sentinel lymph node biopsy was negative. On examination, there were five skin lesions at different stages. Each had spontaneously appeared as a bruise with a central subcutaneous nodule, and the bruising then faded to leave a persistent subcutaneous nodule. Excision of one of the nodules demonstrated a 4.5 mm diameter partly necrotic melanoma deposit in the dermis. CT scan of the head, chest, abdomen and pelvis showed widespread metastases. This rare presentation of cutaneous malignant melanoma metastases has been termed 'sentinel bruising'. There are fewer than 10 cases reported in the literature.

We are all individuals... bioinformatics in the personalized medicine era

The medical landscape is evolving at a rapid pace, creating the opportunity for more personalized patient treatment and shifting the way healthcare is approached and thought about. With the availability of (epi)genome-wide, transcriptomic and proteogenomic profiling techniques detailed characterization of a disease at the level of the individual is now possible, offering the opportunity for truly tailored approaches for treatment and patient care. While improvements are still expected, the techniques and the basic analytical tools have reached a state that these can be efficiently deployed in both routine research and clinical practice. Still, some major challenges remain. Notably, holistic approaches, integrating data from several sources, e.g. genomic and epigenomic, will increase the understanding of the underlying biological concepts and provide insight into the causes, effects and effective solutions. However, creating and validating such a knowledge base, potentially for different levels of expertise, and integrating several data points into meaningful information is not trivial.